Primers Question - Slamfire?

[sfonelson]

I've always purchased CCI 5.56 and CCI 7.62 military primers since I primarily reload for semi autos.

I'm looking to restock on my primers supply and I am looking at regular small and large rifle primers in either CCI, Winchester, or Tul since they are easier to find in stock.

Anybody here have issues with slamfires? I know they "can" happen, but how common is it?

[OpenSightsOnly]

I also load for gas guns.

I use a harder-cupped primer, bump the shoulder back at least 3 thousandths, and use a small base die.

I also check a seated primer.

Tula/Wolf are good - KVB556 and I forget the large primer for 7.62 NATO. Have tried Wolf/Tula large rifle magnum primers.

[koehn,jim]

Slam fires often depend on the rifle. Most US military use a free floating firing pin and that is the problem. When the bolt slams shut the pin moves forward, if you have ever ejected a live round and see a small dimple on the primer that is what happened. Are slam fires common, no but it only takes one to ruin your day. I use military grade primers and small base dies, I had one once and was lucky.

[ocabj]

I've had one slamfire ever out of the tens of thousands of rounds I've fired in the AR platform.

It was a Remington 7-1/2.

Situation: Practicing slow fire 200 yard standing position at my local range (non competition). Single loaded like normal through the ejection port, and dropped the bolt while the rifle was 45 degrees down towards the ground (but in the direction of the target). Round went off. Impact several feet away.

I mention the angle to the ground because protocol dictates closing the bolt with the rifle parallel to the ground and is more 'safe' than the position the rifle was in during the above incident. The angle of the rifle in my opinion had no contribution the slamfire.

That being said, the only primers I've used in the past 7-8 years or so in the AR are:

CCI BR4
Remington 7-1/2
Wolf SRM

I stopped using Winchester SR in 2005 or so because of primer piercing issues

[ocabj]

Note: Had that slam fire I described taken place in an actual match, it would have counted as a shot for record and I would have gotten a score of 0 points for that shot.

[sfonelson]

Thanks for the info guys! It looks like I'll start branching out into other types of primers.

[mjmagee67]

Fingers crossed and knocking on wood. But I've never had a slam fire and use CCI, Winchester, and/or Tula primers for my AR-15's

[mindwreck]

slamfires are not very common. Keep your gun and firing pin clean greatly reduces the chance.

I;ve used CCI TULA and Win primers. +10K of each type from each brand. no problems so far

[Ahhnother8]

When competing, I slide a round into the chamber and drop the bolt, at both 200 and 600 yards. That would account for many thousands of rounds, without a slamfire. All using CCI BR or 450 primers. A bit of grease on the firing pin also does not hurt.